JPH04277573A - New ink composition curable by actinic radiation - Google Patents

Abstract

PURPOSE:To provide an alkali-developable resist ink compsn. which is highly sensitive and excellent in curability and resistance to water, solvent, and heat. CONSTITUTION:An alkali-developable resist ink compsn. which contains a specific resin curable by actinic radiation and a photopolymn. initiator. The resin is obtd. from a specific oxirane compd. prepd. by epoxidizing a dimer of 2,7- hydroxynaphthalene alone or together with beta-naphthol, an unsatd. monocarboxylic acid such as (meth)acrylic acid, and a polycarboxylic acid anhydride.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a new and useful energy beam curable ink composition. More specifically, the present invention includes, as essential components, a specific oxirane group-containing compound, a specific compound having both a functional group that reacts with the oxirane group and an unsaturated double bond, aromatic-, aliphatic-, An energy ray-curable resin comprising a specific energy ray-curable resin (A) obtained by reaction with a compound selected from anhydrides of alicyclic polybasic acids and a photopolymerization initiator (B). The present invention relates to a mold ink composition.

The energy ray curable ink composition of the present invention is extremely useful and suitable for a wide range of uses such as solder resists, etching resists, and plating resists, and is suitable for use in so-called energy rays such as ultraviolet rays and electron beams. It can be cured.

0003

2. Description of the Related Art Photosensitive resin compositions used as solder resists, etching resists, plating resists, etc. in the manufacture of printed wiring boards are extremely useful.

[0004] For example, solder resist has the functions of preventing short circuits during soldering, preventing corrosion of copper in wiring, and providing long-term electrical insulation. However, resin compositions containing epoxy resin as a main component are known as solder resists suitable for such uses.

However, due to the increasing density of printed wiring boards and the expansion of usage environments, the photosensitive resins used for them are required to have high sensitivity, solvent resistance, water resistance, chemical resistance, heat resistance, and electrical properties. Although the demands for various performances are increasing, it is necessary to simultaneously achieve these universal performances.
The reality is that a resin composition that satisfies the requirements has not yet been obtained.

[0006]

[Problems to be Solved by the Invention] In view of these circumstances, the present inventors have developed an energy beam that can be used as various resists and can solve the various problems described above. In order to provide an extremely practical photosensitive ink composition that can be cured and developed with an alkaline solution, we have begun intensive research.

Therefore, the problem to be solved by the present invention is to provide high sensitivity, solvent resistance, water resistance, chemical resistance,
A material that can be cured with energy rays and can be developed with an alkaline solution, which can meet the requirements for various performances such as heat resistance and electrical properties, and which can be used as various resists. An object of the present invention is to provide a highly practical photosensitive ink composition.

[0008]

[Means for solving the problem] Therefore, the present inventors
As a result of intensive studies aimed at the problems that the invention aims to solve as described above, we have developed a compound that has a specific oxirane group-containing compound, a functional group that reacts with the oxirane group, and an unsaturated double bond. A specific energy ray-curable resin (A) obtained by reacting a specific compound with a compound selected from anhydrides of aromatic, aliphatic, and/or alicyclic polybasic acids, and photopolymerization initiation. If an energy ray curable ink composition containing the agent (B) is used,

[0009] Suitable for a wide range of applications such as solder resists, etching resists, and plating resists, it is extremely useful, can be cured by so-called energy beams such as ultraviolet rays and electron beams, has high sensitivity, and is resistant to solvents. that can meet performance requirements such as durability, water resistance, chemical resistance, heat resistance, and electrical properties, and
We have discovered that it is possible to provide an extremely practical photosensitive ink composition that can be used as various resists, can be cured with energy rays, and can be developed with an alkaline solution. Therefore, we have now completed the present invention.

That is, the objects of the present invention are, firstly, to provide an alkaline-developable photosensitive ink composition that can be easily developed with a weak alkaline solution, and secondly, it has good sensitivity and is easily developed by light. The third purpose is to provide an alkali-developable photosensitive ink composition that is cured by a reaction occurring in the alkali-developable photosensitive ink composition, which can be cured not only by light but also by heat. The fourth objective is to provide an ink composition, and the fourth objective is to provide a cured product cured with light and heat, which has properties such as alkali resistance, heat resistance, adhesion, chemical resistance, surface hardness, moisture resistance, and water resistance. An object of the present invention is to provide an alkali-developable photosensitive ink composition that gives an excellent cured product.

That is, the present invention basically consists of an oxirane group-containing compound having a specific structure, a compound having in its skeleton a functional group that reacts with the oxirane group, and an unsaturated double bond; , an energy ray-curable resin (A) obtained by reaction with a compound selected from anhydrides of aliphatic and/or alicyclic polybasic acids, and a photopolymerization initiator (B) as essential components. An energy beam curable ink composition comprising:

0
[012] The present invention specifically relates to general formula [1]

[0013]

[Chemical formula 9]

[However, W, X, Y and Z in the formula are
Hydrogen atoms or formulas, each of which may be the same or different

[0015]

[Chemical formula 10]

It represents the group shown below. however,
A case where all of W, X, Y and Z are hydrogen atoms shall be excluded. ] W of the compound represented by
, X, Y and Z each represent an oxirane group, especially
Oxirane group-containing compounds with a specific structure of glycidyl ether groups or hydrogen atoms (excluding compounds in which all of these W, X, Y, and Z are hydrogen atoms) ), an unsaturated monocarboxylic acid, and an anhydride of an aromatic, aliphatic, and/or alicyclic polybasic acid (A); The present invention provides an energy ray-curable ink composition comprising the agent (B) as an essential component.

[0017] Here, the above-mentioned energy ray-curable resin (A) refers to a reaction product of an oxirane group-containing compound with a specific structure and an unsaturated monocarboxylic acid; Refers to a compound that is reacted with a compound selected from anhydrides of cyclic polybasic acids.

As the resin (A), of course, any resin can be used as long as it is made by reacting various compounds such as those mentioned above, but among them, only the most representative ones are exemplified. First, an oxirane group-containing compound with a specific structure [hereinafter referred to as (a-1)
) shall be treated as such. ] and an unsaturated monocarboxylic acid compound that can react with this oxirane group [hereinafter referred to as (
It shall be treated as a-2). [Hereinafter, this will be treated as (a-3). ] at least one compound selected from anhydrides of aromatic, aliphatic and/or alicyclic polybasic acids (a-
4) and the like.

Among them, the above compound (a-3)
Typical specific polyfunctional epoxy compounds (a-1) used for the preparation of Used together, Part 2
A compound containing an oxirane group via a quantified compound, etc., in which W, X, Y and Z in the compound represented by the above general formula [1] are all glycidyl ether groups or Examples include oxirane group-containing compounds in which each of W, X, Y, and Z is a hydrogen atom (excluding compounds in which all of W, X, Y, and Z are hydrogen atoms).

On the other hand, examples of the unsaturated monocarboxylic acids (a-2) that can react with the oxirane group include acrylic acid, methacrylic acid, crotonic acid, and cinnamic acid. Although these may be used alone or in combination of two or more, it is particularly desirable to use acrylic acid.

Typical examples of the polybasic acid anhydrides (a-4) include maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, hetaconic acid, Hymic acid, chlorendic acid, dimer acid, adipic acid, succinic acid, alkenylsuccinic acid, sebacic acid, azelaic acid, 2,2,4
-trimethyladipic acid,

5-Sodium terephthalic acid, 2-potassium sulfoterephthalic acid, 2-sodium sulfoterephthalic acid, isophthalic acid, 2-potassium sulfoisophthalic acid, 2-sodium sulfoisophthalic acid, dimethyl or diethyl ester. Sulfoisophthalic acid di-lower alkyl esters,

Orthophthalic acid, 4-sulfophthalic acid, 1
, 10-decamethylene dicarboxylic acid, muconic acid, oxalic acid, malonic acid, glutaric acid, trimellitic acid, hexahydrophthalic acid, tetrabromophthalic acid, methylcyclohexentricarboxylic acid or pyromellitic acid anhydrides, etc. .

Of course, these may be used alone or in combination of two or more. Next, to exemplify only particularly representative photopolymerization initiators (B), benzoin and benzoin alkyl ethers such as benzoin or benzoin methyl ether, benzoin ethyl ether or benzoin isopropyl ether;

Acetophenone, 2,2-dimethoxy-2
-phenylacetophenone, 2,2-diethoxy-2-
aceophenones such as phenylacetophenone or 1,1-dichloroacetophenone;

2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone,
anthraquinones such as 1-chloroanthraquinone or 2-alumianthraquinone;

2,4-dimethylthioxanthone, 2,4
- thioxanthone such as diethylthioxanthone, 2-chlorothioxanthone or 2,4-diisopropylthioxanthone;

Ketals such as acetophenone dimethyl ketal or benzyl dimethyl ketal;

002
9] Benzophenones such as benzophenone; or xanthone;
B) can also be used in combination with one or more known and commonly used photopolymerization accelerators such as benzoic acid compounds and tertiary amine compounds.

Furthermore, if necessary, organic solvents can also be used, and examples of such organic solvents include ketones such as methyl ethyl ketone or cyclohexane; aromatic carbonization such as toluene xylene; Hydrogens; cellosolves such as cellosolve or butyl cellosolve;

Carbitol or carbitols such as butyl carbitol; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate or butyl carbitol acetate; Of course, more than one species may be used in combination.

The purpose of using such an organic solvent is to dissolve and dilute the energy ray curable resin (A) described above, apply it as a liquid, and then dry it to form a film. be.

The energy ray curable ink composition of the present invention thus obtained further contains β-hydroxyethyl acrylate, β-hydroxypropyl acrylate, glycidyl acrylate, β-hydroxyethyl acryloyl phosphate, dimethyl aminoethyl acrylate, diethylaminoethyl acrylate,

Ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, propylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate,

Trimethylolpropane diacrylate,
Trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate or tris(
Including 2-acryloyloxyethyl) isocyanurate,

Various methacrylates corresponding to the various acrylates listed above; mono-, di-, tri-acrylates of polybasic acids and hydroxyalkyl (meth)acrylates;
or higher polyesters, or monomers, oligomers or prepolymers having ethylenically unsaturated double bonds, such as bisphenol A type epoxy acrylates, novolac type epoxy acrylates or urethane acrylates; furthermore, barium sulfate,
Various known and commonly used fillers such as silicon oxide, talc, clay or calcium carbonate, etc.

Various known and commonly used coloring pigments such as phthalocyanine blue, phthalocyanine green, titanium oxide or carbon black, and various additives such as antifoaming agents, adhesion agents or leveling agents;

Alternatively, known and commonly used polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, and phenothiazine may also be added.

Furthermore, compounds having two or more epoxy groups in one molecule, such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin or alicyclic epoxy resin, A small amount of an epoxy compound and a curing agent for epoxy resin such as acid anhydrides, amine compounds, imidazole compounds, phenols, quaternary ammonium salts or methylol group-containing compounds,
In combination, by post-heating the coating film, the polymerization of the photocurable component is promoted and copolymerized, thereby improving the heat resistance, solvent resistance, plating resistance, adhesion, electrical properties, hardness, etc. of the composition of the present invention. Various properties can be improved.

The energy ray-curable ink composition of the present invention itself is highly sensitive, and can be dissolved in an alkaline solution before curing, and after curing has good water resistance and solvent resistance. This provides a film with excellent chemical resistance and heat resistance.

[0041] The energy ray as used in the present invention is a general term for ionizing radiation and light such as electron beams, α rays, β rays, γ rays, X rays, neutron beams, and ultraviolet rays.

[0042]

[Example] Next, the present invention will be explained in more detail with reference to Examples, Comparative Examples, Application Examples, and Comparative Application Examples. In the following, all parts and percentages are based on weight unless otherwise specified. Assume that there is.

Example 1 In a flask equipped with a thermometer, stirrer and reflux condenser,
2,7-dihydroxynaphthalene alone or
In addition, 556 g of a tetrafunctional epoxy compound obtained through its dimerization using β-naphthol and 1.3 g of hydroquinone monomethyl ether were charged, and 288 g of acrylic acid and triphenylphosphine were added. 12.8 g was added, and the reaction was carried out at a temperature of 110° C. until the epoxy equivalent became 15,000 or more, to obtain a reaction product (a-3-1).

Further, 152 g of tetrahydrophthalic anhydride was added thereto, and the mixture was reacted at 110° C. until the acid value reached 57 to obtain the desired reaction product. Hereinafter, this will be abbreviated as resin (A-1).

Example 2 In a flask equipped with a thermometer, stirrer and reflux condenser,
844 g of (a-3-1) obtained in Example 1 and 304 g of tetrahydrophthalic anhydride were charged, and the reaction was carried out at 110° C. until the acid value reached 98 to obtain a reaction product.

[0046] Hereinafter, this will be abbreviated as resin (A-2). Example 3 In a flask equipped with a thermometer, stirrer and reflux condenser,
844 g of (a-3-1) obtained in Example 1 and 608 g of tetrahydrophthalic anhydride were charged, and the acid value was 15.
The reaction was carried out at 110° C. until the temperature reached 5 to obtain a reaction product.

[0047] Hereinafter, this will be abbreviated as resin (A-3). Comparative Example 1 In a flask equipped with a thermometer, stirrer and reflux condenser,
"Epicron N-695" with an epoxy equivalent of 213
426 g of ``cresol novolac type epoxy compound manufactured by Dainippon Ink & Chemicals Co., Ltd.'' and 1.3 g of hydroquinone monomethyl ether were added, 144 g of acrylic acid was added, and the mixture was heated at 110°C until the acid value became 3 or less.
The reaction product (d-3-1) was obtained by reacting at a temperature of .

Next, 57% of this (d-3-1) was added to a flask equipped with a thermometer, a stirrer, and a reflux condenser.
0 g and 152 g of tetrahydrophthalic anhydride were added, and 0.5 g of di-n-butyltin diacetate was also added, and the reaction was carried out at a temperature of 110 °C until the acid value reached 78. A cured resin was obtained.

[0049] Hereinafter, this will be abbreviated as resin (D-1). Application Examples 1 to 3 Various components shown below were blended with each of the resins (A) obtained in Examples 1 to 3, and the mixture was kneaded using a roll mill to prepare inks.

Resin (A)

60 parts butyl cellosolve

35 parts benzoin isopropyl ether 3 parts phthalocyanine green
0.5 part
"Modaflow" Leveling agent from Monsanto, USA 1.5 parts ■■■■■■■■■■■
■■■■■■■■■■■■■■■■■■
total
100 copies of the various inks thus obtained were then applied to the entire surface of a copper through-hole wiring board that had been etched in advance, and then dried for 30 minutes at 70°C in a hot air dryer. A test piece with a coating thickness of 30 to 35 microns (μm) was prepared.

Application Examples 4 to 6 Various components as shown below were blended with each of the resins (A) obtained in Examples 1 to 3, and the mixture was kneaded using a roll mill to prepare inks.

Resin (A)
60 parts o-cresol novolac type epoxy resin
10 parts Butyl cellosolve

35 parts Benzoin isopropyl ether 3 parts
phthalocyanine green
0.5 part "Modaflow"
1.5 parts benzyldimethylamine
1.0 part talc

Part 10 ■■■■■■■■■■■■■
■■■■■■■■■■■■■■■■
total
121 copies Each of the inks thus obtained was then applied to the entire surface of a copper through-hole wiring board that had been etched in advance, and then dried for 30 minutes at 70°C in a hot air dryer. A test piece was prepared.

Comparative Application Example 1 A control test piece was prepared in the same manner as Application Example 1 except that resin (D-1) was used instead of (A-1).

Comparative Application Example 2 A control test piece was prepared in the same manner as Application Example 4, except that resin (D-1) was used instead of (A-1).

Each test piece was irradiated with 200 mJ/cm 2 of ultraviolet light having a wavelength of around 365 nm and an illuminance of 10 mW/cm 2 . After exposure, development was performed for 30 seconds at 35° C. with a 1% aqueous sodium carbonate solution using an ultrasonic cleaner to remove the unexposed portions of the coating.

[0056] Then, using a hot air dryer,
Thermal heating was performed at ℃ for 1 hour.

Regarding the various samples obtained, the drying properties of the coating film, the developability with respect to weak alkaline aqueous solutions, the exposure sensitivity,
Coating film hardness, adhesion to substrate, soldering heat resistance, chemical resistance,
Solvent resistance and insulation resistance were evaluated.

The results are summarized in Table 1.

[0059] The evaluation of these various performances was carried out as follows. [Drying property of coating film] Each test piece was dried at 25°C and 65% R. H. After the coating film was allowed to stand for one hour, the presence or absence and degree of tackiness of the coating film was determined and evaluated using fingers.

○: No tack observed at all △: Slight tack observed ×: Significant tack observed [Exposure sensitivity] "Kodak Step Tablet N
o. 2'' (manufactured by Eastman Kodak, a negative film with an optical density difference of 0.15) was brought into close contact with the coating film, and a high-pressure mercury lamp was used to irradiate the film with ultraviolet light at an amount of 200 mJ/cm 2 .

Next, this coating film was subjected to the development test using the weak alkaline aqueous solution described above, and the number of step tablets remaining on the copper foil film was determined. (If you follow this method, the higher the sensitivity, the more steps will remain.) [Coating film hardness] Each test piece is irradiated with ultraviolet light at a light intensity of 200 mJ/cm2 using a high-pressure mercury lamp. did.

Next, the hardness of the coating film was determined according to JIS D-0.
Evaluation was made based on pencil hardness in accordance with 202. [Adhesion to substrate] Each test piece was irradiated with ultraviolet light at an intensity of 200 mJ/cm 2 using a high-pressure mercury lamp.

Next, the hardness of the coating film was determined according to JIS D-0.
202, cross-cuts were made to create 100 cross-cuts, and a peeling test was conducted using cellophane tape, and the state of peeling of the cross-cuts was visually evaluated.

○: No peeling was observed at all △: Peeling was observed at 1 to 20 points out of 100 observation points ×: Peeling was observed at 21 or more points out of 100 observation points [Solder Heat Resistance] Each test piece was irradiated with ultraviolet light at an intensity of 200 mJ/cm 2 using a high-pressure mercury lamp.

Next, the hardness of the coating film was determined according to JIS D-0.
202, it was immersed in a 260° C. solder bath for 20 seconds, and the state of the coating film after immersion was visually evaluated. ○: No abnormalities were observed in the appearance of the paint film. ×: Abnormalities such as blistering, melting, or peeling were observed in the appearance of the paint film. [Chemical resistance] A high-pressure mercury lamp was used for each test piece. Ultraviolet light was irradiated at a light intensity of 200 mJ/cm2.

Next, the samples were immersed in various chemicals as described below under the following conditions, and the appearance and adhesion after immersion were evaluated. Acid resistance: 10% HCl (soaked at 50°C for 1 hour)
Alkali resistance: 10% by weight NaOH (immersed at 30°C for 1 hour) Solvent resistance: trichloroethane (immersed at 30°C for 1 hour) Isopropyl alcohol (immersed at 30°C for 1 hour) And such chemical resistance The evaluation of gender is as follows.

○: No abnormality ×: Dissolution or swelling [Insulation resistance] According to JIS Z-3197, each test piece was heated at 55°C and 95% R. H.
After absorbing moisture for 500 hours under these conditions, the insulation resistance was evaluated as a 1-minute value at 500 VDC using "TR-8601" manufactured by Takeda Riken Co., Ltd.

[0068]

[Table 1]

[0069]

[Table 2]

[0070]

[Effects of the Invention] The energy ray-curable ink composition of the present invention not only has high sensitivity, but also can be developed with a weak alkaline aqueous solution, and has acid resistance, alkali resistance, solvent resistance, soldering heat resistance, and electrical insulation properties. It also has excellent surface hardness and is extremely useful in various application fields such as solder resists, plating resists, and etching resists.

Claims (2)

[Claims] Claim 1: As an essential component, a compound of the general formula [Formula 1] [wherein W,
It represents a group represented by the following formula. However, cases where all of W, X, Y and Z are hydrogen atoms are excluded. A reaction product of at least one oxirane group-containing compound of the compound shown in ] and a compound having both a group that reacts with the oxirane group and an unsaturated double bond; obtained by reaction with an anhydride of a polybasic acid. An energy ray-curable ink composition comprising a resin (A) and a photopolymerization initiator (B). [Claim 2] The above general formula [Formula 3] [However, W, X, Y and Z in the formula may each be the same or different, and each represents a hydrogen atom or a formula [
It represents a group represented by the following formula. However, cases where all of W, X, Y and Z are hydrogen atoms are excluded. ] At least one glycidyl ether group of the compound represented by the general formula [Chemical formula 5] [wherein R1 represents a hydrogen atom or a methyl group, and R2 represents a hydrogen atom, a methyl group, a cyano group, or a halogen group] Atom B1 represents a residue of a polybasic acid. ], and the other glycidyl ether group is a hydrogen atom or the formula [Chemical formula 6] General formula [Chemical formula 7] [However, R1, R2 and B1 are as described above. do. ] or the general formula [Image Omitted] [However, R1 and R2 in the formula are as defined above. The energy ray-curable ink composition according to claim 1, which is substituted with a group selected from the group consisting of the following groups.